Crimson Water Strider

"Normally bugs are for bait, but how could you look into its eyes and even think that?" -Nat Pagle

Riding Requirements:

This mount is available to all eligible characters on your account.
Level 10
Apprentice Riding

Source:

Nat Pagle in Frostwall and Lunarfall. Requires Best Friends with Nat Pagle.
Cost: 100 (reputation discounts apply for some factions)

Notes:

This vivid red version of the Azure Water Strider mount may be obtained in Warlords of Draenor. It is available from Nat Pagle, in your garrison, but he'll only sell it to you if you're one of his Best Friends. The entire process is rather long and complicated!

To access Nat Pagle you must build a Fishing Shack in your Garrison and advance it to level 3.
To advance your friendship with Nat, you can perform quests for him, from both Warlords of Draenor and Mists of Pandaria. See this Wowhead page for more information.
To obtain 100 of Nat's Lucky Coins you have to fish up "lunkers", which are rare variants on regular Draenor zone fish, and turn them in to Nat. The coins are also found as uncommon loot from Cavedweller murlocs in your Garrison's fishing pond in Draenor. The murlocs can be summoned with Lunarfall Carp (Alliance) or Frostdeep Minnows (Horde), which can occasionally be caught from the same pond once you advance your Fishing Shack to level 3. This latter method is probably slower, but there's also a rare chance the murlocs will drop a Sea Turtle or Riding Turtle mount.

Before the addition of Mount Equipment this mount was one of only two that were adept at water-walking. This innate ability was removed from water striders in Patch 8.2.